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Date: Fri, 11 Sep 2015 12:32:35 -0700
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Subject: Re: [Qemu-devel] [PATCH 0/4] target-i386: Don't try to enable
 unsupported TCG features by default
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To: Eduardo Habkost <ehabkost@redhat.com>, qemu-devel@nongnu.org
Cc: Igor Mammedov <imammedo@redhat.com>, =?UTF-8?Q?Andreas_F=c3=a4rber?= <afaerber@suse.de>, Paolo Bonzini <pbonzini@redhat.com>

On 09/11/2015 12:25 PM, Eduardo Habkost wrote:
> This series makes QEMU stop trying to enable an unsupported feature by default
> in TCG mode, avoiding the warnings shown by the (now enabled by default)
> "check" mode.
> 
> To do that, I cchanged the kvm_default_features code to be based on QOM
> properties, and added a new "type" field to allow per-CPU-model KVM defaults to
> be specified.
> 
> Before this series:
> 
>   $ qemu-system-x86_64 -S
>   warning: TCG doesn't support requested feature: CPUID.01H:EDX.de [bit 2]
>   warning: TCG doesn't support requested feature: CPUID.80000001H:EDX [bit 2]
> 
> After this series:
> 
>   $ ./x86_64-softmmu/qemu-system-x86_64 -S
>   [no warning output]

Wouldn't it be easier simply to implement this bit?
It seems like we're simply creating a compatibility mess otherwise.


r~